#include<stdio.h>
#include<stdlib.h>

#define LEFT "["
#define RIGHT "]"
#define LABLE "$"
const char *getusername()
{
    return getenv("USER");
}
const char *gethostname()
{
    return getenv("HOSTNAME");
}
const char *getpwd()
{
    return getenv("PWD");
}

int main()
{
    printf(LEFT"%s@%s %s"RIGHT""LABLE" ",getusername(),gethostname(),getpwd());    
    return 0;
}
